The remains of five S-IVB third stages of Saturn V rockets from the Apollo program are the heaviest single pieces sent to the Lunar surface. Humans have left over 187,400 kilograms (413,100 lb) of material on the Moon, and 380 kilograms (838 lb) of Moon rock was brought back to Earth by Apollo and Luna missions. The only artificial objects on the Moon that are still in use are the retroreflectors for the lunar laser ranging experiments left there by the Apollo 11, 14, and 15 astronauts and by the Lunokhod 1 and Lunokhod 2 missions.[1]

^ abcdefThe ascent stage of Apollo 10 was commanded to fire its engine, left lunar orbit and entered solar orbit. The ascent stage of Apollo 11 was left in orbit and thereafter its orbit decayed and it crashed onto the Moon at an unknown location. The Apollo 16 ascent stage failed to crash onto moon when commanded and it decayed from orbit at a later date and also crashed at an unknown location. The ascent stages of the remaining successful missions (Apollo 12, 14, 15, and 17) were each deliberately crashed onto the Moon. Apollo 13's complete Apollo Lunar Module re-entered Earth's atmosphere after having served as a lifeboat during the aborted mission.

^Astronautix.com, Apollo 13: The S-IVB/IU impacted the lunar surface at 8:10 p.m. EST on April 14 at a speed of 259 meters per second (incorrect, should probably be 2590 meters/sec), […] 137.1 kilometers from the Apollo 12 seismometer.